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                                                                    EXHIBIT 10.9



                           CROSS TIMBERS OIL COMPANY



                           1998 STOCK INCENTIVE PLAN



                        Amended as of February 15, 2000



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                           CROSS TIMBERS OIL COMPANY

                           1998 STOCK INCENTIVE PLAN


                              ARTICLE 1. GENERAL

     Section 1.1 Purpose. The purposes of this 1998 Stock Incentive Plan (the
"Plan") are to: (1) associate the interests of the management of CROSS TIMBERS
OIL COMPANY and its subsidiaries and affiliates (collectively referred to as the
"Company") closely with the stockholders to generate an increased incentive to
contribute to the Company's future success and prosperity, thus enhancing the
value of the Company for the benefit of its stockholders; (2) provide management
with a proprietary ownership interest in the Company commensurate with Company
performance, as reflected in increased stockholder value; (3) maintain
competitive compensation levels thereby attracting and retaining highly
competent and talented directors and employees; and (4) provide an incentive to
management for continuous employment with the Company. Certain capitalized terms
are defined in Section 6.7.

     Section 1.2.  Administration.

          (a)  The Plan shall be administered by the Compensation Committee of
 the Board of Directors of the Company (the "Committee"), as constituted from
 time to time, consisting of two or more members who shall each be an Outside
 Director appointed by the Board of Directors.

          (b)  The Committee shall have the authority in its sole discretion and
from time to time to:

               (i)    designate the executive employees (as defined in Section
          1.3) of the Company eligible to participate in the Plan;

               (ii)   grant Awards provided in the Plan in such form and amount
          as the Committee shall determine;

               (iii)  impose such limitations, restrictions and conditions, not
          inconsistent with this Plan, upon any such Award as the Committee
          shall deem appropriate; and

               (iv)   interpret the Plan and any agreement, instrument or other
          document executed in connection with the Plan, adopt, amend and
          rescind rules and regulations relating to the Plan, and make all other
          determinations and take all other action necessary or advisable for
          the implementation and administration of the Plan.

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          (c)   Decisions and determinations of the Committee on all matters
     relating to the Plan shall be in its sole discretion and shall be final,
     conclusive and binding upon all persons, including the Company, any
     participant, any stockholder of the Company and any employee. A majority of
     the members of the Committee may determine its actions and fix the time and
     place of its meetings. No member of the Committee shall be liable for any
     action taken or decision made in good faith relating to the Plan or any
     Award thereunder.

     Section 1.3. Eligibility for Participation. Participants in the Plan
shall be selected by the Committee from the executive employees of the Company
or its Subsidiaries. For the purposes of this Plan, (i) the term "executive
employee" shall include only employees who are officers, or who are determined
by the Committee, in its discretion, to be key professional, managerial,
administrative, or technical employees or supervisors, and (ii) the term
"Subsidiary" means any corporation or other entity of which at least 50% of the
voting securities are owned by the Company directly or through one or more other
corporations, each of which is also a Subsidiary. With respect to non-corporate
entities, Subsidiary shall mean an entity managed or controlled by the Company
or any Subsidiary and with respect to which the Company or any Subsidiary is
allocated more than half of the profits and losses thereof.

     Section 1.4. Types of Awards Under the Plan. Awards under the Plan may
be in the form of any one or more of the following:

          (i)   Stock Options, as described in Article II;

          (ii)  Incentive Stock Options, as described in Article III; and/or

          (iii) Performance Shares, as described in Article IV.

Awards under the Plan shall be evidenced by an Award Agreement between the
Company and the recipient of the Award, in form and substance satisfactory to
the Committee, and not inconsistent with this Plan. Award Agreements may provide
such vesting schedules for Stock Options and Incentive Stock Options,
performance targets for Performance Shares, and such other terms, conditions and
provisions as are not inconsistent with the terms of this Plan. Subject to the
express provisions of the Plan, and within the limitations of the Plan, the
Committee may modify, extend or renew outstanding Award Agreements, or accept
the surrender of outstanding Awards and authorize the granting of new Awards in
substitution therefor. However, except as provided in this Plan, no modification
of an Award shall impair the rights of the holder thereof without his consent.

     Section 1.5.  Aggregate Limitation on Awards.

          (a)   The maximum number of shares of Common Stock which may be issued
     pursuant to Awards issued under the Plan shall be 6,000,000, of which
     3,000,000 may be issued as Performance Shares. In the aggregate with any
     other stock incentive plan of the Company, the Company may not grant
     Options or Performance Shares such that the total

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     number of shares of Common Stock subject to outstanding Options and
     unvested Performance Shares exceeds 6% of the total number of shares of
     Common Stock that the Company has issued and are outstanding at the time
     any grants are made. In addition, the maximum number of shares that may be
     issued to any individual hereunder pursuant to Options or Performance
     Shares issued hereunder during any one year shall be 600,000 and 300,000,
     respectively, and the maximum number that may be issued to any individual
     pursuant to Options or Performance Shares issued hereunder during the life
     of the Plan shall be 1,200,000 and 600,000, respectively.

          (b)  For purposes of calculating the maximum number of shares of
     Common Stock which may be issued under the Plan in total or to any
     individual:

               (i)   only the net shares issued (e.g., excluding shares
          delivered or withheld for payment of an Option exercise or for tax
          withholding requirements) under the Plan shall be counted when issued
          upon exercise of a Stock Option or Incentive Stock Option or vesting
          of Performance Shares;

               (ii)  only the net shares issued as Performance Shares shall be
          counted as issued (shares reacquired by the Company because of failure
          to achieve a performance target or failure to become fully vested for
          any other reason shall again be available for issuance under the
          Plan); and

               (iii) any shares of Common Stock subject to a Stock Option or
          Incentive Stock Option which for any reason is terminated, unexercised
          or expires shall again be available for issuance under the Plan.

      Section 1.6.  Effective Date and Term of Plan.

          (a)  The Plan shall become effective on the date adopted by the Board
      of Directors, subject to approval by the holders of a majority of the
      votes of shares of Common Stock and Preferred Stock present in person or
      represented by proxy and entitled to vote at the Annual Meeting of
      stockholders of the Company held in 1998.

          (b)  No Awards shall be made under the Plan after the tenth
      anniversary of the effective date of this Plan; provided, however, that
      the Plan and all Awards made under the Plan prior to such date shall
      remain in effect until such Awards have been satisfied or terminated in
      accordance with the Plan and the terms of such Awards.

      Section 1.7. Transferability. The Committee may, in its discretion,
authorize all or a portion of the Stock Options to be granted under Article II
or the Performance Shares to be granted under Article IV to be on terms which
permit transfer by the recipient of such a grant to (i) the spouse, children or
grandchildren of the recipient ("Immediate Family Members"), (ii) a trust or
trusts for the exclusive benefit of such Immediate Family Members, or (iii) a
partnership in which (a) the

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recipient, (b) such Immediate Family Members, (c) corporations, the only owners
of which are such Immediate Family Members or the recipient, or (d) trusts whose
only beneficiaries are such Immediate Family Members or the recipient, are the
only partners, provided that (x) there may be no consideration for any such
transfer, (y) the Award Agreement pursuant to which such Stock Options or
Performance Shares are granted must be approved by the Committee, and must
expressly provide for the transferability in a manner consistent with this
Section, and (z) subsequent transfers of transferred Stock Options or
Performance Shares shall be prohibited except by will or by the law of descent
and distribution. Following transfer, such Stock Options or Performance Shares
shall continue to be subject to the same terms and conditions as were applicable
immediately prior to transfer, provided that for purposes of Sections 2.2 and
4.1 hereof, the terms "Optionee" and "participant," respectively, shall be
deemed to refer to the transferee. The events of termination of employment of
Sections 2.7 and 4.7 hereof shall continue to be applied with respect to the
original Optionee and participant, respectively, following which the Stock
Options shall be exercisable by the transferee only to the extent and for the
periods specified in Section 2.7, and Performance Shares shall vest only to the
extent provided in the Award Agreement.

                           ARTICLE II. STOCK OPTIONS

     Section 2.1. Award of Stock Options. The Committee may from time to time,
and subject to the provisions of the Plan and such other terms and conditions as
the Committee may prescribe, grant to any participant in the Plan one or more
options to purchase the number of shares of Common Stock ("Stock Options")
allotted by the Committee. The date a Stock Option is granted shall mean the
date selected by the Committee as of which the Committee allots a specific
number of shares to a participant pursuant to the Plan.

     Section 2.2. Stock Option Agreements. The grant of a Stock Option shall be
evidenced by a written Award Agreement, executed by the Company and the
Optionee, stating the number of shares of Common Stock subject to the Stock
Option evidenced thereby, and in such form as the Committee may from time to
time determine.

     Section 2.3. Stock Option Price. The option price per share of Common Stock
deliverable upon the exercise of a Stock Option shall be not less than 100% of
the fair market value of a share of Common Stock on the date the Stock Option is
granted.

     Section 2.4. Term and Exercise. A Stock Option may be exercised during the
Option Term and may be subject to such vesting schedule as the Committee may
provide in an Award Agreement. No Stock Option shall be exercisable after the
expiration of its Option Term.

     Section 2.5. Manner of Payment. Each Award Agreement providing for a Stock
Option shall set forth the procedure governing the exercise of the Stock Option
granted thereunder, and shall provide that, upon such exercise in respect of any
shares of Common Stock subject thereto, the Optionee shall pay to the Company,
in full, the option price for such shares with cash. Unless otherwise provided
in the Award Agreement, the Optionee may also pay to the Company, in full, the

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option price with Common Stock owned by the Optionee on the date of exercise or
Common Stock acquired pursuant to such exercise, valued at the fair market value
of a share of Common Stock on the date the Stock Option is exercised, provided
that the Optionee provides satisfactory evidence, in the opinion of the
Secretary or any Assistant Secretary of the Company, that the Optionee directly
owns on the date of exercise shares of Common Stock sufficient to pay the option
price, and that the Optionee has owned such shares for at least six months.

     Section 2.6. Delivery of Certificates. As soon as practicable after
exercise of the Stock Option and receipt of payment, the Company shall deliver
to the Optionee a certificate or certificates for such shares of Common Stock.
The Optionee shall become a stockholder of the Company with respect to Common
Stock represented by share certificates so issued and as such shall be fully
entitled to receive dividends, to vote and to exercise all other rights of a
stockholder.

     Section 2.7. Death, Retirement and Termination of Employment of Optionee.
Unless otherwise provided in an Award Agreement or otherwise agreed to by the
Committee:

          (a)  Upon the death of the Optionee, any Stock Option to the extent
     exercisable on the date of death may be exercised by the Optionee's estate,
     or by a person who acquires the right to exercise such Stock Option by
     bequest or inheritance or by reason of the death of the Optionee, provided
     that such exercise occurs within both (i) the remaining Option Term and
     (ii) one year after such death. The provisions of this Section shall apply
     notwithstanding that the Optionee's employment may have terminated prior to
     death, but only to the extent of any rights exercisable on the date of
     termination of the Optionee's employment.

          (b)  Upon termination of the Optionee's employment by reason of
     retirement or permanent disability (as each is determined by the
     Committee), the Optionee may exercise any Stock Option to the extent
     exercisable on the date of termination of the Optionee's employment,
     provided such option exercise occurs within both (i) the remaining Option
     Term and (ii) one year (in the case of permanent disability) or three
     months (in the case of retirement) after such termination.

          (c)  In the event of the termination of the Optionee's employment for
     cause (as determined by the Committee), all Stock Options shall terminate
     immediately upon the termination of the Optionee's employment.

          (d)  Upon termination of the Optionee's employment by reason other
     than death, disability or cause (as each is determined by the Committee),
     the Optionee may exercise any Stock Option, to the extent exercisable on
     the date of termination of the Optionee's employment, provided such option
     exercise occurs within both (i) the remaining Option Term and (ii) 30 days
     of the date of termination.

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                     ARTICLE III.  INCENTIVE STOCK OPTIONS

     Section 3.1. Award of Incentive Stock Options. The Committee may, from time
to time and subject to the provisions of the Plan and such other terms and
conditions as the Committee may prescribe, grant to any participant in the Plan
one or more "incentive stock options" (intended to qualify as such under the
provisions of Section 422 of the Code) ("Incentive Stock Options") to purchase
the number of shares of Common Stock allotted by the Committee. The date an
Incentive Stock Option is granted shall mean the date selected by the Committee
as of which the Committee allots a specific number of shares to a participant
pursuant to the Plan. Notwithstanding the foregoing, Incentive Stock Options
shall not be granted to any owner of 10% or more of the total combined voting
power of all classes of stock of the Company or its subsidiaries, unless the
Incentive Stock Options (i) have an exercise price of 110% of the fair market
value of the Common Stock on the date of grant, and (ii) the Option Term may not
be longer than five years.

     Section 3.2. Incentive Stock Option Agreements. The grant of an Incentive
Stock Option shall be evidenced by a written Award Agreement, executed by the
Company and the Optionee, stating the number of shares of Common Stock subject
to the Incentive Stock Option evidenced thereby and in such form as the
Committee may from time to time determine.

     Section 3.3. Incentive Stock Option Price. The option price per share of
Common Stock deliverable upon the exercise of an Incentive Stock Option shall be
not less than 100% of the fair market value of a share of Common Stock on the
date the Incentive Stock Option is granted.

     Section 3.4. Term and Exercise. Each Incentive Stock Option may be
exercised during the Option Term and may be subject to such vesting schedule as
the Committee may provide in an Award Agreement. No Incentive Stock Option shall
be exercisable after the expiration of its Option Term.

     Section 3.5. Maximum Amount of Incentive Stock Option Grant. The aggregate
fair market value (determined on the date the Incentive Stock Option is granted)
of Common Stock with respect to which Incentive Stock Options first become
exercisable by an Optionee during any calendar year (under all plans of the
Optionee's employer corporation and its parent and subsidiary corporations)
shall not exceed $100,000.

     Section 3.6.  Death of Optionee.

          (a)  Upon the death of the Optionee, any Incentive Stock Option to the
     extent exercisable on the date of death may be exercised by the Optionee's
     estate or by a person who acquires the right to exercise such Incentive
     Stock Option by bequest or inheritance or by reason of the death of the
     Optionee, provided that such exercise occurs within both (i) the remaining
     Option Term and (ii) one year after the Optionee's death.

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          (b)  The provisions of this Section shall apply notwithstanding that
     the Optionee's employment may have terminated prior to death, but only to
     the extent of any Incentive Stock Options exercisable on the date of
     termination of the Optionee's employment.

     Section 3.7. Retirement or Disability. Unless otherwise provided in an
Award Agreement or otherwise agreed to by the Committee, upon the termination of
the Optionee's employment by reason of permanent disability or retirement (as
each is determined by the Committee), the Optionee may exercise any Incentive
Stock Option, to the extent exercisable on the date of termination of the
Optionee's employment, provided such option exercise occurs within both (i) the
remaining Option Term and (ii) one year (in the case of permanent disability) or
three months (in the case of retirement) after such termination. Notwithstanding
the terms of an Award Agreement, the tax treatment available pursuant to Section
422 of the Code upon the exercise of an Incentive Stock Option shall not be
available to an Optionee who exercises any Incentive Stock Options more than (i)
one year after the date of termination of employment due to permanent disability
or (ii) three months after the date of termination of employment due to
retirement.

     Section 3.8. Termination for Other Reasons. Except as provided in Sections
3.6 and 3.7 or except as otherwise determined by the Committee in an Award
Agreement, all Incentive Stock Options shall terminate immediately upon the
termination of the Optionee's employment.

     Section 3.9. Applicability of Stock Options Section. Sections 2.5, Manner
of Payment, and 2.6, Delivery of Share Certificates, applicable to Stock
Options, shall apply equally to Incentive Stock Options. Said Sections are
incorporated by reference in this Article III, as though fully set forth herein.

                     ARTICLE IV.  PERFORMANCE SHARE AWARDS

     Section 4.1. Awards Granted by Committee. Coincident with or following
designation for participation in the Plan, a participant may be granted
Performance Shares. Certificates representing Performance Shares shall be issued
to the participant effective as of the date of the Award. A holder of
Performance Shares shall have such voting, dividend and other rights of
stockholders of the Company as shall be provided in the Award Agreement.

     Section 4.2. Amount of Award. The Committee shall establish a maximum
amount of a participant's Award, which amount shall be denominated in shares of
Common Stock.

     Section 4.3. Communication of Award. Written notice of the maximum amount
of a participant's Award and the Performance Cycle determined by the Committee,
if any, shall be given to a participant as soon as practicable after approval of
the Award by the Committee. The grant of Performance Shares shall be evidenced
by a written Award Agreement, executed by the Company and the recipient of
Performance Shares, in such form as the Committee may from time to time
determine, providing for the terms of such grant.

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     Section 4.4. Amount of Award Payable. Performance Shares may be granted
based upon past performance or future performance. In addition to any other
restrictions the Committee may place on Performance Shares, the Committee may,
in its discretion, provide that Performance Shares shall vest upon the
satisfaction of performance targets to be achieved during an applicable
Performance Cycle. Failure to satisfy the performance targets may result, in the
Committee's discretion as set forth in an Award Agreement, in the forfeiture of
the Performance Shares by the participant and the return of such shares to the
Company or have any other consequence as determined by the Committee.
Performance targets established by the Committee may relate to corporate, group,
unit or individual performance and may be established in terms of market price
of Common Stock, cash flow or cash flow per share, reserve value or reserve
value per share, net asset value or net asset value per share, earnings, or such
other measures or standards determined by the Committee. Multiple performance
targets may be used and the components of multiple performance targets may be
given the same or different weight in determining the amount of an Award earned,
and may relate to absolute performance or relative performance measured against
other groups, units, individuals or entities. Certificates representing
Performance Shares shall bear a legend restricting their transfer and requiring
the forfeiture of the shares to the Company if any performance targets or other
conditions to vesting are not met. The Committee may also require a participant
to deliver certificates representing unvested Performance Shares to the Company
in escrow until the Performance Shares vest. Notwithstanding the discretion
allocated to the Committee under this Section 4.4, any award of Performance
Shares to the Chief Executive Officer or any other named executive officer, as
listed in the prior year's proxy statement, will comply with the requirements
for qualified performance-based compensation under Section 162(m) of the Code
and the Treasury regulations promulgated thereunder.

     Section 4.5. Adjustments. At any time prior to vesting of a Performance
Share, the Committee may adjust previously established performance targets or
other terms and conditions to reflect events such as changes in laws,
regulations or accounting practice, or mergers, acquisitions, divestitures or
any other event determined by the Committee.

     Section 4.6. Payments of Awards. Following the conclusion of each
Performance Cycle, the Committee shall determine the extent to which performance
targets have been attained and the satisfaction of any other terms and
conditions with respect to vesting an Award relating to such Performance Cycle.
Subject to the provisions of Section 6.3, to the extent the Committee determines
Performance Shares have vested, the Company shall issue to the participant
certificates representing vested shares free of any legend regarding performance
targets or forfeiture in exchange for such participant's legended certificates.
Upon election of the participant on the date of vesting, and upon approval by
the Committee, the Company may purchase some or all of the participant's vested
Performance Shares at the fair market value on the date the Committee determines
that the Performance Shares have vested. Within seven business days after
receipt of the participant's election, the Committee will inform the participant
of its decision whether to approve the purchase of such Performance Shares.

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     Section 4.7. Termination of Employment. Unless the Award Agreement provides
for vesting upon death, disability, retirement or other termination of
employment, upon any such termination of employment of a participant prior to
vesting of Performance Shares, all outstanding and unvested Awards of
Performance Shares to such participant shall be canceled, shall not vest and
shall be returned to the Company.

                         ARTICLE V.  AUTOMATIC GRANTS

     Section 5.1. Grant. Each director who is not an employee of the Company,
its subsidiaries, affiliates and managers ("Non-Employee Director") shall be
granted, on the date on which he or she is initially elected or appointed a
director of the Company, a Stock Option to purchase 2,700 shares of Common Stock
for the fair market price on the date of such grant, for an Option Term of ten
years. Thereafter, on the first business day following the Annual Meeting of
Stockholders of each subsequent year in which the Non-Employee Director is still
serving as a director (whether or not such Non-Employee Director's term has been
continuous), he or she shall automatically be granted a Stock Option to purchase
an additional 2,700 shares of Common Stock for the fair market price on the date
of such grant for an Option Term of ten years. In lieu of the above grants, any
Non-Employee Director that is an advisory director appointed by the Board of
Directors shall be granted Stock Options to purchase 1,350 shares of Common
Stock at the same time, and upon the same terms and conditions as would be
granted to the other Non-Employee Directors under this Section 5.1.

     Section 5.2. Applicable Provisions. The provisions of Section 2.7(a)
relating to the death of an Optionee shall apply to options granted to Non-
Employee Directors under Section 5.1, and the Committee may not agree to the
contrary in an Award Agreement or otherwise. The provisions of Subsections
2.7(b), (c) and (d) relating to disability and other termination of employment
shall not apply to options granted under Section 5.1.

     Section 5.3. Continuation as Director. In the event a Non-Employee Director
stands for re-election as a director of the Company but fails to be re-elected,
such failure shall not affect the Stock Options granted under this Article V. In
all other events where a Non-Employee Director does not continue as a director
of the Company (except for death), the Non-Employee Director may thereafter
exercise only those Stock Options that were exercisable upon the date that he or
she ceased to be a director and only during the period occurring within two
years after such date (but not after the expiration of the Option Term).

     Section 5.4. Effect of Prior Plans. Prior stock incentive plans of the
Company have provided for similar automatic grants to the Non-Employee
Directors, but it is the intent of the Company that duplicate automatic grants
shall not be made.

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                          ARTICLE VI.  MISCELLANEOUS

     Section 6.1. General Restriction. Each Award under the Plan shall be
subject to the requirement that, if at any time the Committee shall determine
that (i) the listing, registration or qualification of the shares of Common
Stock subject or related thereto upon any securities exchange or under any state
or Federal law, or (ii) the consent or approval of any government regulatory
body, or (iii) an agreement by the grantee of an Award with respect to the
disposition of shares of Common Stock, is necessary or desirable as a condition
of, or in connection with the granting of such Award or the issue or purchase of
shares of Common Stock thereunder, such Award may not be consummated in whole or
in part unless such listing, registration, qualification, consent, approval or
agreement shall have been effected or obtained free of any conditions not
acceptable to the Committee.

     Section 6.2. Non-Assignability. Except as permitted by Section 1.7 hereof,
no Award under the Plan shall be assignable or transferable by the recipient
thereof, except by will or by the laws of descent and distribution, and during
the life of the recipient, such Award shall be exercisable only by such person
or by such person's guardian or legal representative.

     Section 6.3. Withholding Taxes. Whenever the Company proposes or is
required to issue or transfer shares of Common Stock under the Plan, the Company
shall have the right to require the grantee to remit to the Company in cash
amounts sufficient to satisfy any federal, state and/or local withholding tax
requirements prior to the delivery of any certificates for such shares.
Alternatively, the Company may allow the participant to submit shares of Common
Stock to satisfy the withholding requirement or may issue, transfer or vest only
such number of shares of Common Stock net of the number of shares sufficient to
satisfy the withholding tax requirements. For withholding tax purposes, the
shares of Common Stock shall be valued on the date the withholding obligation is
incurred.

     Section 6.4. Right to Terminate Employment. Nothing in the Plan or in any
Agreement entered into pursuant to the Plan shall confer upon any participant
the right to continue in the employment of the Company or affect any right which
the Company may have to terminate the employment of such participant.

     Section 6.5. Non-Uniform Determinations. The Committee's determinations
under the Plan (including, without limitation, determinations of the persons to
receive Awards, the form, amount and timing of such Awards, the terms and
provisions of such Awards and the agreements evidencing same) need not be
uniform and may be made by it selectively among persons who receive, or are
eligible to receive, Awards under the Plan, whether or not such persons are
similarly situated.

     Section 6.6. Rights as a Stockholder. The recipient of any Award under the
Plan shall have no rights as a stockholder with respect thereto unless and until
certificates for shares of Common Stock are issued to him (except as to
Performance Shares as provided under Section 4.1).

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     Section 6.7. Definitions. In this Plan the following definitions shall
apply:

          (a)  "Award" shall mean a grant of Stock Options, Incentive Stock
      Options or Performance Shares under the Plan.

          (b)  "Change in Control" means any one of the following:

               (i)    "Continuing Directors" no longer constitute a majority of
                      the Board of Directors of the Company; the term
                      "Continuing Director" means any individual who is a member
                      of the Board of Directors of the Company on the date
                      hereof or was nominated for election as a director by, or
                      whose nomination as a director was approved by, the Board
                      of Directors of the Company with the affirmative vote of a
                      majority of the Continuing Directors;

               (ii)   any person or group of persons (as defined in Rule 13d-5
                      under the Securities Exchange Act of 1934, as amended (the
                      "Exchange Act")) together with his or its affiliates,
                      becomes the beneficial owner, directly or indirectly, of
                      25% or more of the voting power of the Company's then
                      outstanding securities entitled generally to vote for the
                      election of the Company's directors;

               (iii)  the merger or consolidation to which the Company is a
                      party if the shareholders of the Company immediately prior
                      to the effective date of such merger or consolidation have
                      beneficial ownership (as defined in Rule 13d-3 under the
                      Exchange Act) of less than 50% of the combined voting
                      power to vote for the election of directors of the
                      surviving corporation or other entity following the
                      effective date of such merger or consolidation; or

               (iv)   the sale of all or substantially all of the assets of the
                      Company or the liquidation or dissolution of the Company.

          (c)  "Code" shall mean the Internal Revenue Code of 1986, as amended.

          (d)  "Common Stock" shall mean shares of stock which may be issued
     under the Plan that are authorized and unissued or treasury shares of
     common stock, par value of one cent, of the Company.

          (e)  "Fair market value" as of any date and in respect of any share of
     Common Stock means the average of the high and low sales price on such date
     or on the next business day, if such day is not a business day, or if no
     trading occurred on such day, then on the first day preceding such day on
     which trading occurred, of a share of Common Stock traded on

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     the New York Stock Exchange or any other public securities market selected
     by the Committee, provided that, if shares of Common Stock shall not have
     been traded on the New York Stock Exchange or other public securities
     market for more than 10 days immediately preceding such date or if deemed
     appropriate by the Committee for any other reason, the fair market value of
     shares of Common Stock shall be as determined by the Committee in such
     other manner as it may deem appropriate. In no event shall the fair market
     value of any share of Common Stock be less than its par value.

          (f)  "Option" means a Stock Option or Incentive Stock Option.

          (g)  "Optionee" shall mean the holder of a Stock Option or an
     Incentive Stock Option.

          (h)  "Option price" means the purchase price per share of Common Stock
     deliverable upon the exercise of a Stock Option or Incentive Stock Option.

          (I)  "Option Term" shall mean a period of ten years from the date of
     grant thereof in which an Option may be exercised, unless a shorter period
     is provided by the Committee or by another Section of this Plan.

          (j)  "Outside Director" means a director of the Company who (i) is not
     a current employee of the Company; (ii) is not a former employee of the
     Company who receives compensation from the Company for prior services
     (other than benefits under a tax-qualified retirement plan); (iii) has not
     been an officer of the Company; (iv) does not receive remuneration from the
     Company, either directly or indirectly, in any capacity other than as a
     director; and (v) does not possess an interest in a transaction, or is
     engaged in a business relationship, that would require disclosure under
     Item 404(a) or (b) of Regulation S-K promulgated by the Securities and
     Exchange Commission.

          (k)  "Performance Cycle" means the period of time, if any, as
     specified by the Committee over which Performance Shares are vested.

     Section 6.8. Leaves of Absence. The Committee shall be entitled to make
such rules, regulations and determinations as it deems appropriate under the
Plan in respect of any leave of absence taken by the recipient of any Award.
Without limiting the generality of the foregoing, the Committee shall be
entitled to determine (i) whether or not any such leave of absence shall
constitute a termination of employment within the meaning of the Plan and (ii)
the impact, if any, of any such leave of absence on Awards under the Plan
theretofore made to any recipient who takes such leave of absence.

     Section 6.9. Newly Eligible Employees. The Committee shall be entitled to
make such rules, regulations, determinations and Awards as it deems appropriate
in respect of any employee who

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<PAGE>

becomes eligible to participate in the Plan or any portion thereof after the
commencement of an Award or incentive period.

     Section 6.10. Adjustments.

          (a)  In the event of any change in the outstanding Common Stock by
     reason of a stock dividend or distribution, recapitalization, merger,
     consolidation, split-up, combination, exchange of shares or the like, the
     Committee may appropriately adjust the number of shares of Common Stock
     which may be issued under the Plan as Options or Performance Shares and the
     limitations on the maximum number that may be issued to any individual
     during any one year or the life of the Plan, the number of shares of Common
     Stock subject to Options or Performance Shares theretofore granted under
     the Plan, and any and all other matters deemed appropriate by the
     Committee.

          (b)  In the event of a subdivision or consolidation of shares or other
     increase or reduction in the number of shares of the Common Stock
     outstanding without receiving compensation therefor in money, services or
     property, then (i) in the event of an increase in the number of such shares
     outstanding, the number of shares of Common Stock purchasable pursuant to a
     Stock Option granted automatically pursuant to Section 5.1 after the date
     of increase, and the number of Performance Shares granted automatically
     pursuant to Section 5.1 after the date of such increase, shall be
     proportionately increased; and (ii) in the event of a decrease in the
     number of such shares outstanding, the number of shares of Common Stock
     purchasable pursuant to a Stock Option granted automatically pursuant to
     Section 5.1 after the date of decrease, and the number of Performance
     Shares granted automatically pursuant to Section 5.1 after the date of such
     decrease, shall be proportionately decreased.

          (c)  Any such adjustment in outstanding Options will be made with a
     corresponding adjustment in the exercise price per share so that the total
     exercise price applicable to such Options will not change.

     Section 6.11. Changes in the Company's Capital Structure.

          (a)  The existence of outstanding Options or Performance Shares shall
     not affect in any way the right or power of the Company or its stockholders
     to make or authorize any or all adjustments, recapitalization,
     reorganizations or other changes in the Company's capital structure or its
     business, or any merger or consolidation of the Company or any issue of
     bonds, debentures, preferred or prior preference stock ahead of or
     affecting the Common Stock or the rights thereof, or the dissolution or
     liquidation of the Company, or any sale or transfer of all or any part of
     its assets or business, or any other corporate act or proceeding, whether
     of a similar character or otherwise.

          (b)  After a merger of one or more corporations into the Company, or
     after a consolidation of the Company and one or more corporations in which
     the Company shall be the surviving corporation, (i) each holder of an
     outstanding Option shall, at no additional cost, be entitled upon exercise
     of such Option to receive (subject to any required action by

                                      13
<PAGE>

     stockholders) in lieu of the number of shares as to which such Option shall
     then be so exercisable, the number and class of shares of stock, other
     securities or consideration to which such holder would have been entitled
     to receive pursuant to the terms of the agreement of merger or
     consolidation if, immediately prior to such merger or consolidation, such
     holder had been the holder of record of a number of shares of the Company
     equal to the number of shares as to which such Option had been exercisable
     and (ii) unless otherwise provided by the Committee, the number of shares
     of Common Stock, other securities or consideration to be received with
     respect to unvested Performance Shares shall continue to be subject to the
     Award Agreement, including any vesting provisions thereof.

          (c)  Except as herein provided, the issuance by the Company of Common
     Stock or any other shares of capital stock or securities convertible into
     shares of capital stock, for cash, property, services performed or other
     consideration, shall not adversely affect, and no adjustment by reason
     thereof shall be made with respect to, the number or price of shares of
     Common Stock then subject to outstanding Options.

     Section 6.12. Change in Control. If a Change in Control occurs while
unvested Performance Shares or unexercised Options remain outstanding, the
Committee shall waive any limitations set forth in this Plan or any Award
Agreement with respect to such Option or Performance Share such that such Option
shall become fully exercisable and such Performance Share shall vest upon a
Change in Control.

     Section 6.13.  Amendment of the Plan.

          (a)  The Committee may, without further action by the stockholders and
     without receiving further consideration from the participants, amend this
     Plan or condition or modify Awards under this Plan in response to changes
     in securities or other laws or rules, regulations or regulatory
     interpretations thereof applicable to this Plan or to comply with stock
     exchange rules or requirements.

          (b)  The Committee may at any time and from time to time terminate or
     modify or amend the Plan in any respect, except that without stockholder
     approval the Committee may not (i) increase the maximum number of shares of
     Common Stock which may be issued under the Plan or to any individual (other
     than increases pursuant to Sections 6.10 and 6.11), or (ii) change the
     employees or class of employees eligible to participate in the Plan. The
     termination or any modification or amendment of the Plan, except as
     provided in subsection (a), shall not, without the consent of a
     participant, adversely affect his or her rights under an Award previously
     granted to him or her.

     The undersigned hereby certifies that this is a true and correct copy of
the Cross Timbers Oil Company 1998 Stock Incentive Plan, as adopted by the
Company's Board of Directors on April 13, 1998, and the Company's stockholders
on May 19, 1997, as amended.

                                   By:  Virginia Anderson
                                        ---------------------------------
                                        Virginia Anderson, Secretary

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